Submersible pump



Oct. 15, 1940. J. B. HAwLEY, JR

vsummslm: PUMP` original Filed Feb. 22, 195'.'

2 Sheets-Sheet 1 l Saffi/1424343:

Oct. 15, 1940. J, B HAWLEY, JR 2,217,746

SUBMERSIBLE IUMP Original Filed Feb. 22, 1937 2 Sheets-Sheet 200000000000 Qq O 000000000000 w 000000000000 000000000000 OOOOOOOOOQOgwvemlfob OOOOOOOOOOOOOO- @0000000000000 r Jw//f//m/fr/Jff Patented Oct.15, 1940 UNITED STATES 2,217,746 SUBMERSIBLE PUMP John B. Hawley, Jr.,Minneapolis, Minn., assignor to Reconstruction Finance Corporation,Minneapolis, Minn., a. corporation o! the United States ApplicationFebruary 22, 1937, SerlaLNo. 127,674, which is a substitute forapplication Serial No.

91,484, July 20, 1936.

Divided and this appli-V cation July 23, 1938, Serial No. 220,932

y s claims. (ci. a-a7) This invention relates to a portable pump andparticularly to such a pump which may be operated either submerged inthe liquid to be pumped or outside of said liquid. The pump is furtherof the electric motor driven centrifugal l or rotary type. Such pumpsare generally used for pumping liquid from the holds of vessels, frommines and other places where it is convement to lower a pump into theliquid to be pumped.

It is an object of the invention to provide a submersible pump having anovel and eiiicient impeller structure.

It is also an object of the invention to provide a pump comprising acasing having a minimum' of projecting parts.

It is still another object of the invention to provide a pump having anovel means for insuring drainage.

:0 It is still further an object of the invention to provide a pump ofvery compact structure so as to have as short length of impeller shaftprojection as possible.

'I'hese and other objects and advantages of the invention will be fullyset forth in the following description made in connection with theaccompanying drawings, in which like reference characters refer tosimilar parts throughout the several views and in which:

Fig. l is a central vertical section through the main portion of thepump;

Fig. 2 is a partial view similar to Fig. 1 shown on an enlarged scale;

Fig. 3 is-.raview in end elevation as seen from the left of Fig. 2;

Fig. 4 is a view in end elevation of some of the parts shown in Fig. 2;

Fig. 5 is a view in side elevation oi the suction end of the pump withthe inlet valve and strainer secured thereto;

Fig. 6 is an inner end view of the inlet end member of the pump casing;and

Fig. 7 is a view partly in end elevation showing the inner side of themain impeller and partly in vertical section through the vanes of saidimpeller.

Referring to the drawings a pump is shown having a main or centralcasing portion I5. While this portion might be of various forms, in theembodiment of the invention illustrated it is shown as substantiallycylindrical, the same having an outer wall I5a and an inner wall I5b,said walls forming an' annular chamber |50 therebetween and said innerWall forming a central chamber I5d therein. An end member or suctionnozzle I6 is secured to the inlet end of casing I5, said member being oftapering Io'rm toward its outer end and having a cylindrical exteriorlythreaded inlet portion |60, at its outer end of much? less diameter thancasing I5. plurality of recesses about the sides thereof forming shortange portions IBb apertured, to receive headed screws l1 threaded intothe end of casing I5 and which secure member I6 to casing I5. Member I6has on itseinner side helical distribut- 10 ing plates I6d cooperatingwith an impeller to be later described. Casing I5 is provided in its endand adjacent its outer side with an annular groove and member I6 has aprojecting annular rib l6c tting into said annular groove and en- 15gaging a gasket I8 seated in said groove. Gasket I8 is compressed insaid groove by the rib I6c so that a fluid-tight joint is formed. Amotor I5 is disposed in chamber 15d, the same comprising a stator I9aand a. rotor I9b. Said stator :dts against the wall I5d and is engagedat one end by a cup-shaped member 20 and at its other end by\ acup-shaped member 2l. One or more keys 22 are fitted in the inner end ofmember 2,0 and also in the stator so that said members are keyedtogether. Casing I5 is provided with a plurality of recesses I5e at itsouter side, there being only a thickened portion of wall between thebottom of these recesses and chamber I5d. Said portion of wall has aninwardly tapered threaded opening into chamber I5d and headed drainplugs 23 are threaded into said openings. one of said drain plugs havingits end extending into an opening 20a. in member 20. Said latter drainplug therefore functions-to prevent rotation of member 20. It will benoted that the heads of drain plugs 23 are disposed in `recesses I5e andare thusprotected from being struck by any object when the pump is beingsuspended. Wall I5b is provided in its inner side with annular slots inwhich are disposed snap rings 24 and 25. Said rings are substantiallycylindrical but open at one point so that they can be compressed andinserted into said slots and will remain therein by their cxpansiveelasticity? or resiliency. It will be noted that member 2l has a reducedportion extendingalong the inner side of snap ring 24 and thus has ashoulder formed thereon engaging the inner side of snap ring 24. 4\Any'outward stress on member 2| is thus taken by snap ring 24 andtransmitted to the casing wall I5b. Just at the outer side of snap ring24 member 2I is soldered to the inner side of wall I5b `by solder 26,which is preferably silver solder. Member 2i has an inwardly projectingcentral portion bored to re- 55 Member I6 has a 5 ceive and havesecuredtherein a bearing 21 illustrated as of the ball bearing type. A shaft 28is secured to the rotor I 9b by a long key 29, said shaft having aslightly enlarged portion between the end of rotor I9b and bearing 21and having a reduced portion journaled in said Bearing so that ashoulder on said shaft engages the inner side of bearing 21 which thustakes the outward or downward thrust of said shaft. A cup-shaped memberor housing 30 has an open inner end with a groove formed therein fittingover an annular outwardly projecting rib I5f on the outer end of casingI5 substantially alined with inner wall I5d. Member 30 forms an annularpassage I6d with member I6 constituting in effect a continuation ofannular passage I5c. Member 30 has a multiplicity of radially projectinglugs apertured to receive headed screws 3I threaded into the end ofcasing I5 for securing member 30 to said casing. A gasket 32 is disposedin the groove in the end of member 30 and engaged by the rib I5f so thata fluid-tight joint is formed. Member 30 has a central inwardlyextending portion 30a having a cylindrical bore in its outer side toform a cup-shaped recess and portion 30a at its inner side has acentralhub bored to receive a member 33 tightlyi fitting therein andhaving parallel end faces perpendicular to the axis of shaft 28. Member2| also has a shallow bore at its outer side in which is tightly fitteda disklike member 34 having an outer face perpendicular to the axis ofshaft 28. A sealing disk 35 preferably made of carbon tightly surroundsshaft 28 and engages the outer face of disk 34. Another similar disk 36also preferably made of carbon engages the inner face of member 33. Disk36 has projections 36a, extending radially at right angles to each otheras shown in Fig. 3 and disk 35 has similar projections. A cage member 31is provided having a central portion with an inner bore 31a fitting onshaft 28. At either side of said central portion member 31 has anoutwardly projecting cylindrical shell portion 31b and each of saidshell portions has formed in its end slots 31e in which are partiallydisposed the projections 36a. Between bore 31a and its outer side thecentral portion of member 31 llas a plurality of cylindrical bores orholes 31d extending therethrough. Said central portion also has athreaded bore extending radially from the outer side of member 31 tobore 31a and said member is secured to shaft 28 by a set screw 38, asecond set screw 39 also being disposed in said threaded bore andclosing the outer end thereof. Cup washers 40 of thin sheet metalsurround shaft 28 between disks 35 and 36, the same facing said disksrespectively and having lugs 40a thereon extending into compressioncoiled springs 4I disposed in the holes 31d. Holes 31d are shown as ninein number and five of the springs 4I are preferably secured at theirends to one washer 40 while the remaining springs are secured at` theirends to the other washer 40. This facilitates handling of the springs.Each washer 40 has in its cupped side a flanged ring 40a which extendsbeyond the edge of washer 40 and engages the outer portion of aresilient ring 42. Ring 42 has a central portion fitting against shaft28 and this portion is cylindrical at its inner end and is clampedagainst shaft 28 by a ferrule 40h. Ring 42 has a flange or projectingportion at its outer side which bears against disk 35 or 36. From thedescribed construction it will be seen that springs 4I urge washers 4I!away from each other and through the rings 48a press on the outerportions of rings 42 which are in turn pressed against the disks 35 and36 respectively. There is very little outward motion of members 42against the disks 35 and 36 and what motion there is is permittedthrough the flexing of rings 42. The ferrules 40h have been found to bevery important. Without these it was found that relative motion wouldoccur between shaft 28 and rings 42 which would interfere with theproper functioning of the seal. With the present construction thecentral portion of ring 42 is held in fixed position relative to shaft28 and any outward motion of the outer portion of the ring isaccomplished by flexing of the ring. Members 33 and 34 in practice havebeen made of nickel and their faces which are engaged by the disks 35and 36 are made of some extremely hard and noncorrosive metal. Inpractice these disks have been coated with stellite, a composition ofcobalt, chromium and tungsten. Tungsten carbide has also been used. 'Ihedisks 35 and 36 may be made of metal but in practice it has been foundvery suitable to have these made of carbon. A tight seal is thuseffected designed to prevent the passage of any liquid through member 2Ior through member 30. Another disk 43 similar to disks 35 and 36 engagesthe outer face of member 33 at the outer side of member 30. Disk 43 isengaged by a ring 44. A cupped washer 45 receives rings 44a and isengaged at its outer side by a plurality of compression coiled spring 46disposed in cylindrical sockets formed in the inner or upper side of animpeller member 41 having a hub secured to a slightly tapered portion ofshaft 28 by a key 48. Said hub of impeller 41 has a cylindrical flange41h extending inwardly about members 44 and 45, said flange having slotstherein at right angles to each other and receiving projections onmember 43 similar to the projections 36a '\n member 36. Member 43 isthus driven by member 41 just as member 36 is driven by member 31. Shaft28 has a reduced threaded end beyond impeller 41 on which is threaded aclosed nut 49 having an outer rounded end. A spring washer 50 isdisposed between nut 49 and impeller 41. Impeller 41 has inner and outerWalls between which extend a plurality of spaced vanes 41a. The inner orupper wall of impeller 41 is concave and of `conical form. An auxiliaryimpeller 5I is disposed between member 30 and impeller 41, the samehaving a cylindrical hub of a size to be journaled in the bore ofportion 30a. Said auxiliary impeller has a conical wall parallel to theinner surface of impeller 41 and has a plurality of radial blades 5Iaengaging impeller 41 by which it is driven. A pin 5Ib connects impellers41 and 5I so that the latter is driven by impeller 41. It will be seenthat a chamber is formed within member 30 between the impeller or pumpchamber and the motor chainber I5d. Casing I5 has a recess I5g in theside thereof from the bottom of which' an opening extends intotheichamber in member 30, the outer end of said opening being threadedand receiving a threaded plug 52. Said plug has a passage therethroughat its inner end having an enlargement outward thereof forming a valveseat with which a ball valve 53 cooperates. Ball 53 is pressed towardits seat by a coiled compression spring 54. Spring 54 is engaged at itsouter end by plug 55 having a central passage therethrough and held inplace by a transverse pin 56.

The upper end of casing I5 has secured thereto an upper end member 6I).The upper end of casin g I5 adjacent its outer side has an annulargroove therein into which enters an annular rib 60a formed on the end ofmember 68. A gasket 6| is disposed in said groove and engaged by saidrib. Member 50 has a plurality of recesses about the outer side thereofforming short flange porl tions 60h apertured to receive headed screwsor bolts 62 threaded into the end of casing I5 for holding rib Iatightlyagainst the gasket 8| to form a fluid-tight closure. Member SI1-istapered toward its outer end and has a reduced exteriorly threadedcylindrical outlet portion 60e. As shown in Fig. 1 this portion isclosed by a cap 63l threaded onto portion 60o and engaging a gasket 64held between the same and the end of member 68. Cap 63 has secured toand projecting from its outer side a bail handle 63a. The member 28previously referred to has an inwardly or downwardly extending centralportion 20h bored at its inner side to receive a bearing 65 shown as ofthe ball bearing type in which is journaled a vreduced portion of shaft28. Bearing 65 is engaged at its upper or outer side by a disk 65 havinga central portion thinner than its peripheralportion. Disk 86 is engagedcentrally by a screw 61 extending through portion 20h, said screw havinga slotted outer end and carrying a jamb nut 68 engaging the outer sideof portion 20h. Disk 66 has considerable resiliency and shaft 28 is thusheld with some resiliency lengthwise thereof. An annular plate 69extends about an inner side af wall I5b and at its upper or outer sideengages the inner side of snap ring 25. A plurality of circumferentiallyspaced screws 10 are threaded through plate 69 and engage the outer endof member 20. Member 20 as already stated engages theupper end of statorI9a so that the latter is thus held longitudinally in place by screws10. It will be noted that the snap ring 25 takes the outward or upwardthrust caused by the action of screws 19. The endwise thrust or stressof the motor is thus taken at both ends by the snap rings 24 and 25. Anend cover plate 1| has an annular groove adjacent its outer edge fittingover a projection or rib I5h at the upper end of wall I5b and a gasket12 is disposed in said groove and engaged by said projection or rib. Endcover plate 1I has a plurality of lugs at its periphery apertured toreceive headed screws or bolts 13 which are threaded into the end ofcasing I5 and hold said cover plate in place compressing gasket 12 andforming a fluid-tight joint. A stuffing box cover 14 of conicalcup-shaped form is provided having an annular groove at its inner endinto which fits an annular rib or flange 1Ia on cover 1I, a gasket 15being disposed in said groove and engaged by rib 1 Ia. Member 14 has aplurality of lugs at its periphery apertured to receive headed bolts orscrews 16 threaded into cover plate 1I and holding member 14 in placewith gasket 15 compressed to form a fluid-tight joint. Member 14 has arecess at one side thereof with an opening at its bottom leading to theinterior of member 14, said recess being adapted to receive packing 11.The walls of said recess are interiorly threaded and a packing gland 18is screwed therein compressing said packing about a cable cover orsleeve 19 passing through said gland and through said opening intomember 14. Cable 19 covers a plurality of conductors 19a, one of whichis shown as secured to the upper side of cover 1| by a screw 80 andanother of which is shown clamped between nuts 8| threaded onto a rod 82forming a binding post and extending through cover 1 I. Rod 82 hassecured thereto at the inner side of cover plate 1| a plurality ofconductors 83 held in place thereon by nuts 84 and passing through aninsulating bushing 83a in member 20. An insulating bushing 85 surroundsrod 82 and is tightly fitted in cover 1I and passes therethrough, thesame being enclosed at its outer side by another insulating plug ormember 86. Rod or binding post 82 is thus insulated from cover 1I.Member 6I) has a cup-like projection 60d at its upper side adapted toreceive packing 81. Member 19 passes outwardly through an opening inmember 68 through the packing 81 and through a packing gland 88 threadedinto portion 60d and compressing packing 81 about member 19. Gland 88has an outer portion 88a threaded to receive a pair of headed screws 89extending through a clamping cap 90 overlying cable sleeve 19 so thatthe latter is clamped in position by the clamping cap 90. Scr'ews 89 aswell as screws I1, 3|, 62, 13 and 16 are shown as having split springwashers 9| beneath the heads thereof. Member 60 is shown as having aring lug 60e at one side thereof. 1

In Fig. 5 the pump casing, particularly end member I6, is shown ashavingthreaded thereon and secured thereto an inlet valve member 92. SaidValve member has secured at its outer or lower end a strainer member 93.Members 92 and 93 per se form no particular part of the invention andneed not be further described.

The pump can be conveniently transported by using the handle 63a whencap 63 is in place and the pump is not in pumping operation. Whenthepump is to be used cap 63 will be removed and the discharge hose orconduit will be connected to portion 60o. The pump can be lowered` intothe hold of a vessel or other desired place by a cable secured in thelug 60e. When it is desired to operate the pump the motor I9 will bestarted by current supplied through the conductors 19a which will becontrolled by a suitable switch. Rotor I9b rotates and shaft 28 isdriven. Impeller 41 is rotated and water is drawn through the strainer93, through the valve 92 which is a regular pump check valve and saidwater passes from impeller 41 into the annular chamber between membersI6 and 39. The water is directed against the distributing vanes I8d onmember I6 which assist the flow and distribution of the water and thewater passes upwardly through annular chamber I5c, through the annularchamber between members 14 and 80 which alines with passage or chamberI5c and the water then passes out through the end of member 6'0 and isdischarged in the desired place by the attached conduits. The auxiliaryimpeller 5I is driven by impeller 41 and discharges any liquid which mayhave passed into the cylindrical chamber in portion 30a. By having thedischarge passages of the impellers directed upwardly the averageeffective diameter of the auxiliary impeller 5I is greater than theaverage diameter of the main impeller 41. The effective diameter ofimpeller 41 would be that at the lower outer edge or substantially alonga line extending from said edge perpendicular to the center line of thedischarge passage. The fluid pressure on the seal member 43 is thuseither zero or less than zero or in other words, there is a partialvacuum in the chamber in portion 30a. This vacuum reaches about fivepounds when the pump is operating at zero pressure and is at zero whenthe pump discharge is shut off. It will be seen from this that theauxiliary impeller 5| thus acts to draw out any liquid from portion 38aand will draw out and discharge any fine particles of dirt or foreignmatter which might work through the running fit between the cylindricalportion of impeller 5| and the bore in portion 30a. When the pump isrunning, therefore, there is no tendency for the liquid to pass into thechamber in portion 30a and thus to work past the seal members 43 or 36.It will be seen that by having the auxiliary impeller 5| that thepressure on the sealing members 33 and 34 is substantially zero and thatthere is a negative pressure on these members at all times when the pumpis operating or when the motor' i running. The seals are subjected to amaximum pressure equal to the submergence pressure'when the pump is notrunning. The auxiliary impeller thus constitutes means for limiting thepressure on the sealing members to a small percentage of the dischargepressure of ythe pump.

It will be noted that by having the springs 46 housed in the impeller4,1 the structure is made quite compact lengthwise of shaft 28. 'I'hiseliminates extra parts and saves space lengthwise of the pump. This ishighly important since the shaft overhang from theglower bearing 21 mustbe kept as short as possible. It is also pointed out that members 30 andI6 each has one single annular sealing gasket. This results in astructure where both gaskets can be kept tight. It is quite diicult tohave two parallel gaskets on one part and keep both tight. 'I'he innergasket 32 is quite inaccessible and it is all the moreimportant' to havethis gasket kept tight. Members 68, 1| and 'I4 also have only a singlegasket and the above remarks apply to these members. Gaskets |6c, 32,60, 'Ha and 12 are of resilient material, preferably containing cork.Members I6, 30, 60, 'Il and 14 are drawn down to a metal to metalcontact at the sides of the gasket grooves, thus assuring concentricassembly, the engaging edges being disposed in planes perpendicular tothe centralaxis of the parts. The member 'I4 encloses a terminal chamberindependent of the chamber at the inner side of member 1|. This forms aconvenient chamber for the distribution of the conductors 'and aconvenient connection for a ground conductor for grounding the casing ismade by the screw 8U. A tight andinsulating seal is made by thetelescoping members 85 and 86 which are clamped on member 1| by the nuts84 and 8|. The cable member 79 is flexible so that no strain is put onmember 14 by any exterior stresses on the cable. Should any water leakinto the chamber in member 14 about the cable, this water can be removedby removing member 14 Without removing member 'Il and thus breaking theseal into the motor chamber. By having the recesses |58 and |5g theplugs therein are protected from striking exterior objects in thehandling of the pump. Should the pressure in the chamber between members2| and 30 exceed the outside pressure and any water kbe in Said chamberit will lift ball valve 53 and pass out through plug 52. The pressurewithin member 30 therefore cannot exceed the exterior or submergencepressure plug the pressure of spring 54.

The motor unit is held by members and 2|. These members react againstthe snap rings 24 and 25 so that the end thrust is taken by the casingwall. No end thrust of the motor due to holding it in place or due toexpansion and contraction of the parts due to temperature can place anypressure on member 1| and thus cannot affect the seal between member 1|and wall |5b of the casing. It should also be noted that no endwisepressure is exerted on the solder 26 since the end thrust of member 2|is taken by snap ring 24. The action of screw 81 on' resilient disk 66holds shaft 28 under a slight reslliently yleldable pressure. Thisprevents any axial displacement of the shaft which might disturb theaccurate positioning of the sealing disks 35, 36 and 43 or which mightdisturb the proper positioning and clearances of the impellers. Theyielding pressure exerted on shaft 28 also acts to prevent any hammereiect due to a shock to the pump due to dropping or other cause.

It is pointed out that since sealing members 36 and 43 are urged inopposite directions against member 33 that one of these members will beurged to sealing position by the pressure whether the pressure ispositive or negative in the chamber within member 38. The springs of oneof the sealing members will thus always act with the pressure. It isimpossible to balance or adjust a spring pressure'for a wide range ofpositive and negative pressure With the described arrangement as abovestated one seal always acts with the pressure whatever the pressure inthe adjacent chamber. By having member 33 made with parallel sealingfaces this part can be made with extrme accuracy. This results in a veryeiicient seal.

By having gland member 88 constitute the cable clamp the necessity for aseparate or auxiliary cable clamp is eliminated.

From the above description it is seen that applicant has provided a verysimple and highly efficient pump. 'I'he pump is designed to withstandthe rigorous use to which it is put when submerged at considerabledepths. The motor is protected from the liquid to be pumped and ismounted in a very ecient manner. The parts are all contained within theouter wall of the casing. The pump has been amply demonstrated in actualpractice, found to be very successful and efficient andlis beingcommercially made.

This application is a division of applicants copending application, S.N. 127,674, filed February 22, 1937, which was a substitute forapplicants copending application S. N. 91,484, led July 20, 1936.

It will, of course, be understood that various changes may be made inthe form, details, arrangement and proportions of the parts, withoutdeparting from the scope of applicants invention, which generallystated, consists in a device capable of carrying out the objects aboveset forth in the parts and combinations of parts disclosed and definedinthe appended claims.

What is claimed is:

1. A pump of the submersible type having in combination, a casing havinga chamber with an inlet at one end and a sealing chamber adjacent saidchamber, a shaft extending longitudinally and centrally of said casingand through said chambers, means for driving said shaft, an impellersecured to said shaft adjacent said inlet and an auxiliary impellerdisposed inwardly of said impeller to discharge any fluid which mightpass inwardly thereof, said casing having a centrai hub at the lower endof said sealing chamber having a cylindrical bore closed at its upperend and forming an auxiliary` sealing chamber, said auxiliary impellerhaving a hub journaled in said bore.

2. A pump of the submersible type having in combination, a casing havingan inlet at one end, a shaft extending longitudinally and centrally ofsaid casing to a point adjacent said inlet, means for driving saidshaft, an impeller secured to said shaft having an outwardly directedinlet opening and discharge passages flaring upwardly, means forming anauxiliary sealing cihamber above said impeller and an auxiliary impellerdisposed inwardly of said impeller and having an inlet passage extendingupwardly and having an open upper end communicating with said auxiliarysealing chamber and having discharge passages extending radially andupwardly.

3. A pump of the submersible, type having in combination, a casinghaving an inlet at one end, a shaft extending longitudinally andcentrally of said casing to a point adjacent said inlet, means fordriving said shaft, a main impeller secured to said shaft having adownwardly directed inlet opening with an upwardly and outwardlydirected discharge passage, means forming an auxiliary sealing chamberabove said impeller, an auxiliary impeller disposed inwardly of saidimpeller and having an inwardly directed inlet opening communicatingwith said auxiliary sealing chamber to maintain a negative pressuretherein.

4. A pump of the submersible type having in combination, a casing havingan inlet at its lower end, a shaft extending longitudinally andcentrally of said casing to a point adjacent said inlet, means fordriving said shaft, an. impeller secured to said shaft having dischargepassages flaring upwardly and having a conical inner surface slopingdownwardly toward the axis of said shaft, said casing having meansforming an auxiliary sealing chamber above said impeller and anauxiliary impeller having blades fitting against said surface to formpassages therewith, said auxiliary impeller thus having upwardlyextending discharge passages and having an inlet opening communicatingwith said auxiliary sealing chamber.

5. A pump of the submersible type having in combination, a casing havingan end chamber with inlet opening at one end, a shaft extendinglongitudinally of said casing, an impeller secured to said shaftadjacent said inlet opening, said casing having a sealing chamberinwardly of said chamber, a sealing means about said shaft inwardly ofsaid impeller, an auxiliary sealing chamber between said impeller andrst mentioned sealing chamber and an auxiliary impeller between saidimpeller and sealing means for maintaining a low pressure on saidsealing' means and in said auxiliary sealing chamber when said pump isoperating.

6. A pump of the submersible type having in combination, a casing havinga chamber with an inlet opening at one end, a second chamber forcontaining a driving means and a sealing chamber between said chambers,a shaft extending longitudinally of said casing, means in said secondchamber for driving said shaft, an impeller secured to said shaftadjacent said inlet opening, a sealing means surrounding said shaftbetween said first mentioned chamber and sealing cham- 55 ber and aplurality of springs urging said means to sealing position, saidimpeller having recesses therein for receiving said spring.

'7. A pump of the submersible type having in combination, a casinghaving inner and outer walls forming an annular chamber therebetween, ashaft extending axially of said casing, a partition within said innerwall through which said shaft passes forming the bottom of a motorchamber in said casing, a second casing having an open-ended cylindricalportion of substantially the same diameter as said inner wall, meanssecuring said second casing to said first mentioned casing, said innercasing having a chamber therein forming a sealing chamber between itslower end and said partition, said shaft extending through said secondcasing, sealing means about said shaft at said partition and lower endof said second casing, a propeller secured to said shaft below saidsecond casing, a third casing having a cylindrical portion ofsubstantially the` same diameter as said outer wall and forming acontinuation thereof, .means securing said third casing to saidrstmentioned casing, a 'gasket between said third casing and saidrstmentioned casing, said third casing tapering toward its lower end andhaving a cylindrical open' end forming an inlet passage for the iiuidmoved by said impeller, which uid passes between said second and'thirdcasings and between said innen-and outer walls, whereby said thirdcasing may be removed and access had to said propeller Without breakingsaid sealing means.- A

L 8. A pump'of the submersible type having in combination, a casing'having inner and outer walls forming an annular chamber therebetween, ashaft extending axially of said casing, a partition within said innerwall through which said shaft passes and forming the bottom of a motorchamber, a bearing for said shaft in said partition, a second casinghaving an open-ended cylindrlcalportion of substantially the samediameter as said .inner wall, means securing said second casing to saidfirst mentioned casing, a gasket between said casings, said secondcasing having a chamber therein. forming a sealing chamber and having1 alower end through which said shaft passes,`means for sealing theopenings for said shaft through said partition and second casing, athird casing having a cylindrical open end of substantially the samediameter as said outer wall and forming a continuation thereof, meanssecuring said-thlrdcasing to said rst mentioned casing, a gasket betweensaid third casing and said first .mentioned casing, said third casingtapering toward its lower. end and having a reduced cylindricalopen-ended portion at its lower end, a propeller secured to said shaft between said secondand thirdcasings, said second and third casingsforming a passage communicating with the passage through said inner andouter Walls through which the liquid is moved by said propeller, wherebysaid third casing may be removed and access had to said propellerwithout breaking said sealing means.

JOHN B. HAWLEY, Jl.

